Buildings, particularly those having flat roofs, may include parapets or comparable structures extending above their roof lines on one or more sides. These parapets typically perform dual functions, themselves enhancing the aesthetic appearance of the building while preventing rainwater and other fluid contaminants from flowing from the roof onto the adjacent building faces. Blocking the flow of fluids also helps preserve the building appearance by reducing discoloration of the building faces, for example, and assists in maintaining the structural integrity of the facial components as well.
Because the parapets are exposed to the atmosphere, they too may require protection from moisture and other pollutants. Copings thus have been developed to cover, or cap, the relatively horizontal upper surfaces of parapets. These copings, currently (at least) virtually exclusively made of metal, are designed to extend the width of the upper surface of the parapets and redirect fluid away from the upper surface. Among the simplest coping is a single solid aluminum or other metallic sheet measured (on-site) and cut (typically off-site) to fit a particular upper parapet surface and nailed to the upper surface or a galvanized steel base. If the width of the parapet surface is not uniform, however, the tasks of cutting and fitting the metallic sheet to create a fluid-tight seal are often both difficult and time consuming. Unless the metallic sheet is inclined, moreover, it may not effectively redirect fluid with which it comes in contact.
U.S. Pat. No. 4,964,248 to Braine, et al. recognizes that parapet wall widths are frequently non-uniform throughout their lengths. Consequently, the Braine patent discloses a multi-piece coping assembly in which a top plate and a fascia member may be telescoped. Such telescoping permits adjustment of the width of the coping assembly, thereby better accommodating varying parapet thicknesses as a function of their length. According to the Braine patent, a resilient clamping means holds the top plate in place, including opposing surfaces of the fascia member and a clip member which engage in multiple locations to interconnect the components. The patent does not disclose satisfactory guttering action should fluid seep beneath the top plate, however, nor does it discuss covering joints where, for example, parapet walls meet at an angle.
U.S. Pat. No. 4,083,158 to Wolma, by contrast, discloses an adjustable mounting plate onto which a single-sheet coping may be mounted. The two-piece mounting plate is nailed to the parapet surface so as to span the parapet width at selected points. Subsequently, the single-sheet coping may be shaped as necessary to fit the series of mounting plates and ultimately snapped into place. Like the Braine patent, the Wolma patent (both of which are incorporated herein in their entireties by this reference) fails to address guttering problems caused by fluid seepage beneath the coping's upper surface and leakage which sometimes may be present at either straight or curved joints.